EXTREMA RATIO Extremely Good Knives

Hi all, well today I received 3  knives from EXTREMA RATIO for coming video field reviews and I’m going to start to preview them here in this blog. I hope what you read here will give you good background about this company's knives, at least the following models. I’ll give a general overview and then discuss each model on it’s own.

They are:

EXTREMA RATIO DobermannIV

EXTREMA RATIO Task

EXTREMA RATIO ONTOS SURVIVAL KNIFE

I’ve been following the progress of the Italian company EXTREMA RATIO  for some years now since its inception back in 1997 and I've got to say EXTREMA RATIO's knives are quite apart from anything you may have seen, fantastic  practical design and the finish which is exceptional right down to the boxes they are supplied in.

First observations:

All models came deadly razor sharp and I mean deadly as some cosmic surgical blade can only be! Not only were they deadly sharp but when I examined each edge at over X10 magnification, this is what I saw: 

Knife Edge at greater than lifesize note few grind marks

These knives were sent out of the factory with almost POLISHED edges! Beat that! There were almost no grind marks visible and that was reflected (no pun intended) in the mirror reflection from the edge! 

Now I know that these blades are hand finished and this clearly shows the dedication and workmanship of staff at EXTREMA RATIO. The other thing I observed straight away was that the bevelled edge was not some skimpy steep angled grind. This latter kind of knife bevel often found on mass produced knives from automated sharpening (or even if it isn’t automated grinding ) results in an edge that has limited cutting ability and will not last very long  and if the blade is used at shallow angles, it won't bite into the material you are trying to cut (That’s just plain  physics!)

How about the comfort? Not too many manufacturers are willing to enter into this discussion. Not so with EXTREMA RATIO.

What did I find? Unbelievable comfort and ergonomics! Seriously! This comes as no surprise, but I needed to experience it first hand. EXTREMA RATIO entered into a collaboration with the Motor Sciences department at the University of Perugia  for the design of the handles. 

Ok you ask what is Motor Science? It's kinesiology! This is the research of the mechanics of motion with respect to human anatomy. Smart move here from EXTREMA RATIO and as far as I am aware at the time of writing this article no other knife manufacturer does this.

Despite all three knives here being of different design, when I started swinging each knife (A test I always perform without wearing a glove or tying the knife to my hand with a lanyard) at no point during a powerful downward (and of course upward) swinging arc did these knives feel as if they were going part company with my hand. Now this is partially due to the frictional properties of the material the handles are made from, which is FORPRENE. The Forprene EXTREMA RATIO are using is a composite (glass fibre) with a Shore hardness of 80-90. However, a major influencing factor is the actual handle design. This grippy design feels great. That's right first impressions!  The end of the handle decreases slightly in size, NOT increases, so a swinging motion will tend not to open your last two fingers. The top and bottom profiles are rounded and the sides are partially flattened to provide a resistance to a twisting motion.

Forprene Composite handle

You know a lot of manufacturers put a lot of effort into the blades but not the scabbards or the actual handles, thinking, a handle is a handle and let's just bolt on some composite slabs and be done with it. NOT so here.

What did EXTREMA RATIO say about it to me:

The handle design was a result from a collaboration between the University of Perugia's Motor Sciences Department (see above).
For handle materials they collaborate with the Faculty of Engineering at the University of Florence, where tests are made on materials, structures and finishings.

Ok so FORPRENE is an absolutely industry proven elastomeric polymer. It is made right here in Italy from the S.O.F.T.E.R company. It’s has an extremely wide use in all sorts of industries. It can be manufactured to give a wide range of physical characteristics along with fantastic chemical resistance, even to some polar solvents, high resistance to stress (like impact) and abrasion, temperature extremes from approximately -50C to +125C!  and highly resistant to the effects of UV radiation! The handle colour is available in two choices, black or an Olive drab colour.

The handling ergonomics is also due of course to the actual blade geometry, ie it’s weight distribution and centre of gravity. Again we cannot ignore physics in the design of a great blade. This is a company where they have no problems in showing the public what tests they perform on their knives, test data/images, previous models and of course destruction test data. Why? Because they have absolute confidence in their products, that’s why. Backing this up is of course a lifetime warranty on EXTREMA RATIO knives. Serialized blades and a special lot number accompanying each knife, so that in the unlikely event of a manufacturing defect, the blade can always be traced.

Construction

EXTREMA RATIO state that all fixing metallic parts such as bolts etc “are virtually immune from oxidation”. Again what manufacturers are stating this in writing?

Blackening process

All of the above models came to me with a blackened blade. This is the Mil-C-13924 chemical blackening process that imparts a non-reflective surface.

Anti-Reflection Black Mil-C-13924

Don’t get hung up by thinking it improves the blades resistance to oxidation- it doesn’t really and as EXTREMA RATIO state: “Superficial coatings” (such as blackened blades) still need to be maintained. Common sense but it is written down in the “Ordinary maintenance” pamphlet that comes with every knife.

I should point out here that the Dobermann IV also comes with a polished surface finish and leather sheath system. The shiny surface may appeal to those who would like to use their knife, should the situation arise, to signal for help etc. something impossible to do with a blackened blade. On this note a blackened blade is much less obtrusive in a civilian situation, ie wilderness camping/hiking and personally this is something that is playing a significant role these days with increasing rules and regulations on knife usage around the world.

Sheaths

Sheaths are all well designed and the stitching is very nice and even. There is nothing weak looking. The Dobermann IV even came with an extra plastic reinforced retention strap, presumably when the first one wears out (more on this in a later blog!). I couldn’t fault the scabbards  and that’s why they carry a whopping 6 year warranty! Who is warranting their sheaths like this? As I said I'll review the sheaths on an individual basis later, this blog is just to whet your appetite!

Of course EXTREMA RATIO are manufacturers of knives for military usage so again it was no surprise that all of the above models could be inserted and removed ABSOLUTELY silently into their scabbards/sheaths.

Let's start with the:

ONTOS Survival Knife

What a great name! From the Greek, meaning “THING” and this knife is a “SomeTHING” for sure!

Survival knives, wow what can be said here? Generally people start thinking of hollow handle RAMBO style knives, or knives based on similar design sporting vicious looking (and mostly ineffectual) saws or what manufacturers would have you believe are saws. Have you ever tried using them?

I’ve had these hollow handle knives in my hands both expensive and cheapo. The biggest problem is not actually the hollow handle but the lack of ergonomics of a metal hollow handle (that has to be made strong enough) against justifying placing a few “survival items” inside this handle and a pommel, which, if you damage it, either you will not be able to retain your precious “survival stuff” or not be able to unscrew it to retrieve your materials! Plus there generally isn’t a lanyard hole on these types of knives, so what happens if you drop it down a hole because you can't secure it. Sorry, a lanyard hole IS mandatory on any knife being marketed as a "survival knife". Hollow handle knives, to be strong enough to resist breakage due to levering action must be made from metal. How about using these kinds of knives in sub zero temperatures without gloves? No chance or with an ambient temperature of 30C and above? Burnt or stuck fingers I bet!

The ONTOS a knife that can truly carry the label of Survival Knife!:

The ONTOS was designed from the ground up.

What do I think about the design?

As I said above, the knife is very ergonomic due to it’s balance of weight and the design of the FORPRENE handle. There is a lanyard hole so if you are working at height or over a crevasse or simply somewhere that if you drop your knife you will loose it (river, lake, cave, coastal shore etc) then this is not a problem. The use of Forprene means that your hands will not freeze to the handle in sub-zero conditions, nor will it burn from the heat of the desert, if this knife is left even for seconds in the blazing sun.

The butt end 

Pommel region and lanyard hole

is that same for all EXTREMA RATIO fixed blades  which, could be used as a glass breaker. The extension and design of the butt means you wont be damaging yourself on some sharp bit of metal. For glass breaking it’s just not necessary to have a sharp butt end glass breaker but for some reasons many manufacturers design knives like this. Full marks to EXTREMA RATIO here for thinking this out. Just another of their well thought out design features.

The blade is thick where it needs to be 

ONTOS Spine view

and has powerful feel to it. It has a simple edge geometry. It's a convex grind on the cutting edge for superior edge strength compared with a basic flat beveled edge. The blade shape makes for easy field sharpening, or in unskilled hands (maybe someone with you when the sh*t hits the fan may have to use your knife if you are incapacitated and maybe that person has no or little skill in sharpening knives. Simple blade geometry is crucial for anyone trying to market a knife under the label of “Survival” The ONTOS certainly passes this test of mine. 

ONTOS Specifications at a glance

The cutting tip is a western style Tanto. The main blade edge is slightly convex. Now this latter point means despite this being a heavy duty knife, the edge design is perfect for light weight food prep by a simple rocking motion of the blade. Pretty smart eh?!

There is a false edge at the tip running back about 67mm to a section of full thickness spine for a distance of about an inch or 25mm. This is followed by a section of deadly sharp (but shallow in height) serrations. Shallow serrations are less likely to sustain damage if they sustain a striking blow. Serrated edges ARE great for rapidly cutting ropes  and any fibrous materials plus slicing through man made materials such as rubbers and plastics. 

Spine Serration's

No nonsense thumb/finger rest

There is a generous  area to rest your thumb on. I measured a 

spine thickness of about 6.38mm which runs to 11mm from the tip! You are not going to bust this tip! Despite it’s heavy appearance the ONTOS is not what I would call a heavy knife weighing in at 406 grams/14.3 Ozs, with full survival kit at 1kg. The survival kit and diamond sharpener (installed in a side pocket on the optional survival kit pouch)

Diamond impregnated sharpening surface, use with water

Sharpening Instructions

weigh in at 290gm, so the scabbard and pouch weigh approximately 304 grams.

I should point out here that the Survival kit is NOT a product by EXTREMA RATIO but of the brand BCB International. A quick word  here on it’s contents.

BCB Survival Kit Not from Extrema Ratio

The aluminium container is just ok. The contents like all of these types of kits is very ma ma and I’ll be getting rid of certain objects, and replacing with first aid gear, as for me in a survival situation, first aid is paramount. But more on the survival kit in a later blog and the video field review.

N690 EXTRA  Blade Material and Heat Treatment

Like all fixed blade EXTREMA RATIO knives (except the Landing Force, made of Ti alloy) the ONTOS has a Rockwell of 58. EXTREMA RATIO choose a Rockwell of 58 because for N690 this provides the best stainless corrosion performance and sharpening qualities.

 All EXTREMA RATIO blades are heat treated in a specialized  external facility using a vacuum-sealed furnace and heat reduction is carried out in a similar facility with a Nitrogen forced pressure treatment.

N690 EXTRA  from the Austrian company BÖHLER-UDDEHOLM AG, which by the way has been renamed to Voestalpine Edelstahl GmbH.

N690 (you can read all about here by following the link) is a Cobalt stainless steel of exceptional qualities for high end knife steel manufacture. I've been using several knives made with N690 for the past 3 years and they really hold an edge plus are great for working in or around watery environments, resisting corrosion. It's tough and can really take a beating.

The overall width of the blade is about 43 mm, fairly constant along it’s entire length, of which the latter is about 165/166mm or about 6.5 inches.

The full-length tapered tang (see below)

Full tang

is a mechanically proven design of EXTREMA RATIO’s but those in doubt will have to wait and see my field test of the ONTOS. The Forprene handle is fixed to the tang, like all EXTREMA RATIO fixed blades by  corrosion resistant bolts, 

Corrosion resistant handle fixing bolts

which can be simple undone with either a flat blade screw driver type blade or an Allen wrench. Note that the fixing bolt is the only hole in the tang other than the hole for the lanyard. This hole too is set some distance back from where there might a bending moment, ie there is plenty of solid steel between actual knife blade and handle fixing bolt.

There are plenty of places to strike a fire steel and the one inch section on the spine will enable you to baton with this blade without damaging the serrations (if you have to baton- where noise is not a problem ie not to disclose your position/frighten game or maybe your environment’s combustible materials don’t need to have the daylights beaten out of them to start a fire).

The carry system of the ONTOS

The functionality of the sheath is unbelievable! I mean it’s great! Let me tell you about it.

Side view with optional Survival Kit from BCB

Front outside view shown with Molle Survival kit
attachment

Backside view showing fully adjustable leg strap and carry loop
along with Molle attachments for direct pack transporting

The scabbard is fully MOLLE compatible both front and rear. Excellent stitching and attention to detail only instal user confidence in this carry system.

To remove the survival pouch you must first remove the survival kit and diamond sharpener. This will enable you to bend the pouch to access the 2 press studs to undo them. Once undone then slide the MOLLE straps out of the loops. This is a very tight fit and you may need to prise with a blunt object, the MOLLE loops, to allow the height of the press studs to pass under them. It’s not a problem and better like this than a sloppy fit especially if you are on the run/move! The last thing you want is a sloppy system. More on the carry system in the coming video reviews.

Buying an EXTREMA RATIO knife is a good investment when it comes to a product you can rely on.

Let’s face it, you really do get what you pay for and what is worth more? Your life or the cost of a knife at the end of the day? It doesn’t matter whether you are:

in combat or simply out in the middle of nowhere, if you are relying on your equipment to keep operating and safe from harm, whatever that maybe, then better to not have to think about whether the knife you took with you could fail you.

Once you start to doubt your equipment then you’re really in trouble.

 Up next the TASK from EXTREMA RATIO!